acme-tiny VS cert-manager

Going to throw another hat into the ring here: I use acme-tiny [1], which is a single file ACME client written in Python in under 200 lines. The idea behind it is that you can fully read and understand everything it does without spending too much time on it. I really like this approach, so I went ahead and started using it, and have been for a few years now.

[1] https://github.com/diafygi/acme-tiny

Let’s Encrypt with ACME-Tiny

Recommendation from me as well. Have been using this script for multiple years now without a single issue. The minimal code is awesome for avoiding unnecessary external dependencies and complexity.

Be sure to use the latest version from https://github.com/diafygi/acme-tiny though :-)

cert-manager

The second one is a combination of tools: External DNS, cert-manager, and NGINX ingress. Using these as a stack, you can quickly deploy an application, making it available through a DNS with a TLS without much effort via simple annotations. When I first discovered External DNS, I was amazed at its quality.

On top of its core components, SpinKube depends on cert-manager. cert-Manager is responsible for provisioning and managing TLS certificates that are used by the admission webhook system of the Spin Operator. Let’s install cert-manager and KWasm using the commands shown here:

terraform { required_providers { kubectl = { source = "gavinbunney/kubectl" version = "1.14.0" } } } # The reference to the current project or a AWS project data "google_client_config" "provider" {} # The reference to the current cluster or EKS data "google_container_cluster" "my_cluster" { name = var.cluster_name location = var.cluster_location } # We configure the kubectl provider to use those values for authenticating provider "kubectl" { host = data.google_container_cluster.my_cluster.endpoint token = data.google_client_config.provider.access_token cluster_ca_certificate = base64decode(data.google_container_cluster.my_cluster.master_auth[0].cluster_ca_certificate) } #Download the multiple manifests file. data "http" "cert_manager_crds" { url = "https://github.com/cert-manager/cert-manager/releases/download/v${var.cert_manager_version}/cert-manager.crds.yaml" } data "kubectl_file_documents" "cert_manager_crds" { content = data.http.cert_manager_crds.response_body lifecycle { precondition { condition = 200 == data.http.cert_manager_crds.status_code error_message = "Status code invalid" } } } # We use the for_each or else this kubectl_manifest will only import the first manifest in the file. resource "kubectl_manifest" "cert_manager_crds" { for_each = data.kubectl_file_documents.cert_manager_crds.manifests yaml_body = each.value }

SSL certificates thanks to Cloudflare and cert-manager

kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/${CERT_MANAGER_VERSION}/cert-manager.crds.yaml

put the Sub-CA inside hashicorp vault to be used for automatic signing of services like https://cert-manager.io/ inside our k8s clusters.

install-cert-manager: desc: Install cert-manager deps: - init-cluster cmds: - kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/{{.CERT_MANAGER_VERSION}}/cert-manager.yaml - echo "Waiting for cert-manager to be ready" && sleep 25 status: - kubectl -n cert-manager get pods | grep Running | wc -l | grep -q 3

I've been pretty frustrated with how private CAs are supported. Your private root CA can be maliciously used to MITM every domain on the Internet, even though you intend to use it for only a couple domain names. Most people forget to set Name Constraints when they create these and many helper tools lack support [1][2]. Worse, browser support for Name Constraints has been slow [3] and support isn't well tracked [4]. Public CAs give you certificate transparency and you can subscribe to events to detect mis-issuance. Some hosted private CAs like AWS's offer logs [5], but DIY setups don't.

Even still, there are a lot of folks happily using private CAs, they aren't the target audience for this initial release.

[1] https://github.com/FiloSottile/mkcert/issues/302

[2] https://github.com/cert-manager/cert-manager/issues/3655

[3] https://alexsci.com/blog/name-non-constraint/

[4] https://github.com/Netflix/bettertls/issues/19

[5] https://docs.aws.amazon.com/privateca/latest/userguide/secur...

the Cert Manager